But Miami soon began its own streak. After splitting their next two games, the Heat kicked off what has stretched into a 22-game winning streak, tying them for the second-longest streak in NBA history with the 2007-08 Houston Rockets. (The longest is 33 games in a row by the ’71-72 Lakers.)

Monday night, Miami and Boston reunite in TD Garden. A national television audience again will tune in. And the Celtics, already short Rondo, again could be down a key player, another leader, as veteran center Kevin Garnett is questionable to play because of a left adductor strain.

Coach Doc Rivers said that Garnett, who missed Saturday night’s game and didn’t practice Sunday, is “50-50 at best” to play because of the injury, which is located in the thigh area.

Rivers stressed that the injury wasn’t that serious, “but it’s just a point in the year where you’re not going to play him if he’s not feeling great.”

That statement alone suggests that the Celtics, who already have rested Garnett in one game this season, are thinking more about preparing for the playoffs than they are Miami.

Rivers added of Garnett’s injury, “Even if he missed a couple games, it’s not an injury that’s a big deal. I’m not that concerned about it.”

Garnett has missed two games this season, one at Phoenix (rest) and again Saturday night against Charlotte; the Celtics won both of those games, the first by 25 points, the second by 17. So it’s not as though they don’t know how to win without Garnett.

However, each of those opponents are simply horrible, unlike Miami, which will be playing its third game in four nights and its second of a back-to-back.

The defending champions have won their 22 straight games by an average of 12.1 points, with seven wins coming by 16 or more points.

In the last few days, the Celtics have chimed in about the Heat’s dominance. The consensus response: Meh.

Jason Terry: “Not really impressed with anything they do. So, for me, it’s more about what our team is doing and how we’re coming together as a unit.

Paul Pierce: “I really don’t even care. I hope they lose every game the rest of the season. I just worry about what this team does.”

Jeff Green: “I don’t care about a winning streak. We’re going in to try to win a game.”

Coincidentally, Monday night’s game falls on the five-year anniversary of the game when the Celtics snapped Houston’s 22-game winning streak.

However, Rivers pointed out a key difference between that Houston team and this Miami team: Houston was flying under the radar; Miami is the defending champion.

As such, the Heat receive every opponent’s A game — every night.

“That’s what makes their streak so impressive to me, is they’re getting the best from teams — and still winning,” Rivers said.

The key differences Rivers said he’s noticed about the Heat during their streak is their improvement on defense and that Dwyane Wade, who has dealt with several injuries over the course of this season and last, seems to be healthy.

“Wade is a different player,” Rivers said of the veteran guard, who is averaging 23.9 points during the streak, with four games of 30 or more.

And then there is LeBron James, whom Rivers said the Celtics plan to defend with several players. “He’s too smart to have one coverage and one man,” Rivers said.

The Celtics likely will throw Avery Bradley, Pierce, Green, and Brandon Bass on James at different times while mixing in zone and man-to-man defense.

James, who is averaging 26 points, 7.5 assists, and 8.1 rebounds during the streak, scored 34 points, grabbed 16 rebounds, and had 7 assists when these teams last played.

If Garnett misses the game, the Celtics will go to a small lineup with only one big man — Bass or Chris Wilcox — on the floor at any given time.

Though the game carries magnitude, Rivers tried not to overplay it, saying the Celtics already know they can beat Miami so they don’t really have anything to prove.

But the Celtics can prove that their last win against Miami was no emotional fluke, that they can beat one of their playoff rivals and the NBA’s most powerful team without not just one but potentially two stars.

Such an emphatic, streak-snapping Celtics victory would send a message, one that would resonate if these teams happen to meet up, once again, in the playoffs.